Most fungi are saprophytic and not pathogenic to plants, animals and humans. However, a relative few fungal species are phytopathogenic, cause disease (e.g., infections, allergies) in man, and produce toxins that affect plants, animals and humans. Among such fungi are members of the Aspergillus and Fusarium genera as well as other genera (e.g., Alternaria, Mucor) comprising the emerging pathogen group in humans. These fungi present a common threat to both agricultural production and the health of healthy and immunocompromised individuals. Taken together, these relative few fungi can cause huge economic losses to agriculture, loss of food for consumption, and serious, often fatal diseases in humans and animals. Plants may be a source of antifungal compounds since they have had to develop compounds to resist infections by fungi present in their environment.